package practice;

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		int[] arr = new int[5];
		String str = null;
		Scanner sc = new Scanner(System.in);
		while(true) {
			String choice = sc.next();
		
			try {
				if(choice.equals("arr")) {
					int index = sc.nextInt();
					arr[index] = 1;
				} else if(choice.equals("null")) {
					str.length();
				} else if(choice.equals("cast")) {
					Object o = new String("str");
					Integer x= (Integer)o; 
				} else if(choice.equals("num")) {
					String intNum = sc.next();
					Integer.parseInt(intNum);
				} else{
				break;
			}
			}catch(Exception e){
				System.out.println(e);
			}
				
			}
			
				
	}

}
